[RC5] Cracking 40 bits in realtime

Greg Wooledge wooledge at kellnet.com
Fri Jan 2 20:05:07 EST 1998

gindrup at okway.okstate.edu (gindrup at okway.okstate.edu) wrote:

>      Also, don't forget to try pretty much every decompression you can 
>      think of since most *real* encryptors prefer to compress before 
>      encrypting.

Ah!  So, in addition to matching English (or the originator's language)
letter/word frequency tables, do a quick match of the first few bytes
of each decrypted message against the magic numbers found in /etc/magic.

Obviously, that would slow things down a bit.

# Greg Wooledge                         # "Daddy, why do those people have to
# wooledge at kellnet.com                  #   use Microsoft Windows?"
# http://kellnet.com/wooledge/main.html # "Don't stare, son; it's not polite."
#        --  Crack RC5-64 now! http://www.distributed.net/rc5/  --
To unsubcribe, send 'unsubscribe rc5' to majordomo at llamas.net
rc5-digest subscribers replace rc5 with rc5-digest

More information about the rc5 mailing list